Smart devices such as smartphones or tablet terminals are rapidly spreading. These types of smart devices are different from a conventional personal digital assistant (PDA) or a conventional notebook computer, and have various functions such as an application program execution function, a communication function, and an imaging function. Accordingly, this type of smart device is often used for personal use as well as for the work of a user, and introduction of bring your own devices (BYODs) spread with the spread of smart devices. Specifically, when an in-company network provided in a company building of a place of work of a user includes a wireless local area network (LAN), a smart device owned by the user is connected to the in-company network via the wireless LAN and used for the work of the user.
In the BYOD, in order to prevent intrusion of virus into the in-company network or indiscretion, it is common to permit only a terminal device satisfying a predetermined security policy to connect to the in-company network. It is common for the smart device to connect to the in-company network via a wireless LAN included in the in-company network. Therefore, a quarantine system corresponding to a wireless network system such as a wireless LAN is required to realize the BYOD for the smart device. The quarantine system is a system for checking if a terminal device attempting to connect to the in-company network satisfies a predetermined security policy. Related art regarding this type of quarantine system includes the technology disclosed in Patent Literature 1 or Non-Patent Literature 1.
In Patent Literature 1, it is described that the in-company network is logically divided using a virtual local area network (VLAN), and one of the VLANs plays the role of a “quarantine VLAN”. According to the technology disclosed in Patent Literature 1, when the terminal device connects to the in-company network, the terminal device first connects to the quarantine VLAN and checks if the terminal device satisfies the security policy, the terminal device connects to a VLAN for work when the terminal device satisfies the security policy, and thus, quarantine of a personal terminal is realized. Meanwhile, Non-Patent Literature 1 discloses a technology for preventing the leakage of confidential information by installing, in the terminal, dedicated software that monitors a connection destination in real time, identifying whether the connection destination is an in-company network or another network such as a general public line, and switching, for example, the communication setup of the terminal according to an identification result (for example, web access to outside of the company during connection to the in-company network is prevented).